The present invention relates to a liquid filled vibration isolator for use in, for example, an engine mount of a vehicle.
The conventional liquid filled vibration isolator of this type has, as shown in FIG. 8, for example a rubber member 2 coupled on the upper end side of a cylindrical member 1, and the rubber member 2 is provided with a fitting member 3 fixed coaxially to the cylindrical member 1. The cylindrical member 1 has a thin rubber member coated part 4 disposed continuous to the rubber member 2 on the inner peripheral surface thereof, and has an orifice member 5 and a diaphragm member 6 disposed on inner peripheral portion of the lower end side thereof from inside sequentially in the axial direction. The orifice member 5 and the diaphragm member 6 thus close the lower end side opening portion of the cylindrical member 1, and tight seal a liquid chamber E provided between them and the rubber member 2. In addition, by drawing the lower end side of the cylindrical member 1 (diameter-reducing processing) thereof, the orifice member 5 and the diaphragm member 6 are fixed to the cylindrical member 1.
Meanwhile, in the above-stated liquid filled vibration isolator, the orifice member 5 and the diaphragm member 6 are fixed to the cylindrical member 1 only by the reactive force of the rubber member coated part 4 resulting from the drawing of the cylindrical member 1. Due to this, there is a fear that the diaphragm member 6 and the like slip out of the cylindrical member 1 as a result of, for example, the fatigue of the rubber member coated part 4 if the vibration isolator are used for a long period of time.